Process of obtaining nitrobenzylanilin.



' UNITED STATES BENNO HOMOLKA, OF FRANKFORT-ON-THE-MAIN, AND AUGUST STOCK, OF

HOOHST-ON-THE-MAIN, GERMANY, ASSIGNORS TO THE FARBWERKE, VOR- MALS MEISTER, LUOIUS & BRllNING, OF HOOHST-ON-THE-MAIN.

PROCESS OF OBTAINING .NITROBENZYLANILIN.

SPECIFICATION forming part of Letters Patent No. 636,043, dated October 31, 1899.

Application filed December 15, 1897.

To all whom it may concern:

Beit known that we, BENNO HOMOLKA, doctor of philosophy, a citizen of the Empire of Austria-Hungary, residing at Frankfort-onthe-Main, Germany, and AUGUST STOCK, doctor of philosophy, a citizen of the Empire of Germany, residingv at Hochst-on-the-Main,

- Germany, haveinvented certain new and useful Improvements in the Manufacture of Or- IO thoand Para-Nitrobenzylanilin and its Homologues, (for which we have obtained Letters Patent in Germany, No. 97,847, dated June 28, 1896; in France, N0. 260,329, dated June 10, 1896, and in England, No. 22,041,

dated October 5, 1896,) of which the following is a description.

This invention relates to the production of orthoand para-nitrobenzylanilin and its homologues.

According to the researches of Wachendorff, Haeusermann and Beck, Loesner, and

others, the corresponding nitrobenzyl chlorid or nitrobenzyl-bromid of the general formula (where w represents the halogen atom) is obtained by the action of chlorin or bromin,

0 with or without application of the so-called carriers of halogen upon orthoor para-nitrotoluene atahigh temperature. A quantitative chlorination or bromination of the two nitro-toluenes into nitrobenzyl chlorid or bro- 3 5 mid is, however, not possible in this Way, as

Serial No. 662,031. (No specimens.)

researches of A. Baeyer and E. & O. Fischer, color manufacturers soon entered this promis-- ing field, and attempts have not been wanting within the last ten years to arrive at the separation of the pure nitrobenzyl haloid from the said raw chlorination or bromination prod- 5 5 ucts. A satisfactory solution of this problem is still unknown.

By the action of anilin or its homologues or with naphthylamin upon the nitrobenzyl haloids the nitrobenzyl bases of the general formula e rn-NH-orn-o nnvo, are obtained. We have found that the nitrobenzyl bases can easily be transformed by oxidation into the corresponding nitrobenzylidene compounds of the general formula which latter compounds are split up bydiluted 7o mineral acids into amido bases and nitrobenzylaldehyde. The problem of separating the pure nitrobenzylchlorid from the abovementioned raw chlorination or bromination product began to be of renewed interest for them. We succeeded in carrying out this separation in a practical manner by indirect means-namely, by obtaining the pure nitrobenzyl bases from the raw chlorination or bromination products of the two nitrotolu- 8o enes. The nitrobenzylanilin bases have been obtained formerly by the action of pure nitrobenzylchlorid upon anilin and its homologues. (See Watts Dictionary, p. 541.) This process, however, has nothing in common 8 5 with ours, as both are distinguished from each other'by employing a different primary material.

The invention may be characterized in the following Way: By means of incomplete chlo-' 9o rination or bromination of the orthoor paranitrotoluene at the temperature of about 120 to l'centigrade, with or without carriers of halogen there is obtained, as already mentioned, a mixture of orthoor-para-nitroben- 5 zyl chloridor bromid and unchanged orthoor para-nitrotoluene on chlorinating or brominating, for instance, up to fifty per cent.-

i. 0., the fifty per cent. chlorination product.

to one molecule of the existing nitrobenzylchlorid) is allowed to act on this mixture under heat a reaction takes place, expressed by the following equationthat is, there is obtained a mixture of hydrochlorid of anilin, nitrobenzylanilin, and unchanged nitrotoluene. The hydrochlorid of anilin is removed by extracting the residue with water, whereupon the unchanged nitrotoluene is obtained in a pure state by distilling the residue with steam. The nitrobenzylanilin, which, as has been found, is not volatile in vapor, remains behind, and can at once be employed for manufacturing nitrobenzylaldehyde.

The process is carried out in the following manner: A spacious boiler-like vessel of copper or cast-iron, provided with a rapidlyworking agitator and means for distillation and for heating with steam,is filled with three hundred kilos of an orthoor paranitrotoluene chlorinated up to fifty per cent, corresponding to about one hundred and seventy kilos of orthoor para-nitrobenzyl chlorid and one hundred and ninety kilos of anilin or the equivalent quantity of toluidine or yxlidine or a mixture of these bases. The mixture is heated to to centigrade, whereupon combination takes place according to the equation given above, manifesting itself by the rapid rising of the temperature of the mixture to from to centigrade, (according to the choice of the anilin base.) As soon as the highest temperature is reached and the thermometer begins to fall the reaction is completed. The mixture is allowed to cool down to about 90 centigrade, three hundred liters of water are added, and the whole is boiled, whereupon the formed hydrochlorid of anilin dissolves and may be drawn off. The insoluble residue, consisting of nitrobenzylanilin and nitrotoluene, is distilled Nitroben zylanilin with steam, when the nitrotoluene distils over in a pure state and serves for a new chlorination. The nitrobenzylanilin remains behind and can be purified, if need be, by crystallization from alcohol or dissolving in dilute acids and by reprecipitation.

In the above example, first, for the nitrobenzyl chlorids maybe substituted the equivalent quantity of the corresponding nitrobenzyl bromid; second, for the anilin or its homologues may be substituted to a certain extentthat is to say, one-half fixed alkali, alkali carbonate or acetate, alkaline earth or ammoniain which case an addition of fifty to one hundred liters of water is advisable.

Having now described our invention, what we claim is The herein-described process of producing orthoand para-nitrobenzylanilin which consists in heating theknown mixture of nitrobenzylchlorid and nitrotoluene, as obtained by the incomplete chlorination of a nitro toluene Where the nitro group is notin the meta position,with bases of the anilin series, whereby the hydrochloric acid formed by the reaction is bound by the addition of a salt-forming base, and then separating the nitrobenzyl base from the mixture by treatment with Water and distillation with steam, substantially as set forth.

In testimony that we claim the foregoing as our invention we have signed our names in presence of two subscribing witnesses.

BENNO I-IOMOLKA. AUGUST STOCK. Witnesses:

HEINRICH HAHN, ALFRED BRISBOIS. 

